Wrench



May ,1 6- D. T. MLSON 2 042,131

WRENCH Filed Nov. 18, 1935 Patented May 26, 1936 UNITED STATES PATENT OFFICE 1 Claim.

The invention relates to the style of wrench generally referred to as a chain" wrench. In this type a chain is passed around the pipe or other object to be grasped, which chain cooperates with a toothed jaw portion of a handle to 5 which it is permanently connected at an end and detachably engageable with a tooth or claw carried by said jaw portion. 4

The general objects of the present invention are to improve the structure and operation of a wrench of this character so as to render it serviceable and eflicient in use, and more particularly to render it facile of application to an object to be turned and equally facile of release from the object.

According to the present invention, in order to make the wrench easy to apply and release,

the tooth or claw is swingably attached to the jaw portion and shouldered so that it may have a limited movement to and away from the jaw. m This enables it to be shifted mm register with the link that is nearest in alignment to it when the chain is passed around the article to be grasped. As the handle is moved in the proper direction to turn the article, the tooth or claw is drawn back against a shoulder so as to tighten the chain and to cause the jaw to obtain a secure r p.

When the article has been turned to the required extent the wrench can be released without difliculty by moving the handle backwardly, which movement causes the tooth or claw to swing away from the shoulder in order that the curved extremity may be freed from the engaged link.

In'the conventional chain wrench the tooth or claw is rigid with the handle, and after the turning operation it is dlfllcult to disengage the chain owing to the jaw biting into the article turned. The pivotal tooth or claw of the present invention overcomes this objection and facilitates and expedites manipulation of the wrench.

The accompanying drawin is illustrative of the preferred construction of the invention in which:

Figure 1 is a side elevation of the wrench grasping a pipe. g

Figure 2 is a similar view in which the tooth or claw is depicted in its released position and the engaged link is shown in section.

ure 2 omitting the chain.

Like numerals of reference indicate corresponding parts in each of the figures throughout the drawing of the invention.

'In the drawing, the numeral 5 denotes the handle which may as customary consist of a flat- Figure 3 is a cross section on line 3-3 of Figsided bar of suitable length having a grip portion at one end by which it is handled. The other end is formed into an enlarged jaw 6 having an arcuate edge face curved away from the forward part I to which the end 8 of the llnkchain 9 is permanently united.

The arcuate edge face is. supplied with sawshaped teeth l arranged to grip in the forward movement of the handle.

The tooth or claw II is pivoted at l2 adjacent to the toothed edge and at the rearward part of the handle with respect to the path of travel of the handle in turning an object. The tooth or claw has a curved terminus i3 for engaging in a link of the chain, which terminus is free to swing in an arc of a circle. A shoulder i4 provides a limiting stop as shown in the drawing. However such shoulder may be otherwise constructed or modified within the scope of the invention. For instance the bifurcated body l may be utilized as a limiting stop if so desired.

It will be readily understood that in the use of the tool the tooth or claw can be readily swung into engagement with a coinciding link after the chain has been passed around the object to be turned. The tooth or claw is drawn by the tightening of the chain into abutting engagement with the shoulder i4. Upon turning the object, the tooth or claw can be readily freed by a slight reverse movement of the handle which causesthe chain to slacken and thus shifts the terminus l3 away from the shoulder as illustrated in Figure 2.

What I claim is:

A wrench of the class described comprising a flat-sidedbar forming a handle, said bar having an arcuate enlargement at an end thereof commencing at the forward edge and receding therefrom, the said enlargement projecting directly outwardly from the rearward edge and having 40 an abrupt inner face perpendicular to the length of the bar so as to constitute an abutment shoulder, saw-shaped teeth formed on the arcuate face of the enlargement for gripping in the forward movement of the handle, a link chain having an end connected to the forward edge portion of said enlargement and the other end free, and a bifurcated claw pivoted to the rearward edge portion of the bar adjacent to said abutment shoulder and arranged to swing backwardly into contact with said abutment transversely of the handle in the tightening of the wrench, the distal end of said claw being curved away from said abutment shoulder and adapted to engage in the links of the chain.

, DAVID T. WILSON. 

